Water-soluble polyalkylenepolyamine/dialdehyde resins and application thereof in production of wet strength paper



United States Ratent O 3,372,086 WATER-SOLUBLE POLYALKYLENEPOLY-AMINE/DIALDEI-IYDE RESINS? AND AP- PLICATION THEREOF IN PRODUCTION OFWET STRENGTH PAPER Paul M. Westfall, St. Albans, and Nelson R. Eldred,South Charleston, W. Va., and John C. Spicer, Sidney, N.Y., assignors toUnion Carbide Corporation, a corporation of New York No Drawing. FiledApr. 14, 1965, Ser. No. 447,980

' 14 Claims. (Cl. 162-164) ABSTRACT OF THE DESSCLOSURE A cationicWater-soluble resinous reaction product of (a) a polyfunctionalhalohydrin and (b) a resin produced by reaction of apolyalkylenepolyamine with a saturated aliphatic dialdehyde of 2 to 6carbon atoms. The product is useful in paper products as Wet strengthimproving agents. The method for incorporation of the novel polymers inpaper products as well as the paper products are also novel.

This invention relates to novel cationic water-soluble resinouscompositions. More particularly, this invention relates to novelcationic water-soluble polymers produced by reacting apolyalkylenepolyamine with a saturated aliphatic dialdehyde andpartially cross-linking the resulting product with a polyfunctionalhalohydrin. In a specific aspect, the invention relates to theincorporation of the novel polymers in paper products as wet-strengthimproving agents and comprehends both the improved paper products andmethods of producing such products from aqueous suspensions ofcellulosic paper-making fibers.

Conventional cellulosic paper products lose their strength rapidly whenwetted; for example, the wet strength of ordinary paper is only aboutfive to ten per cent of its dry strength. To .overcome thisdisadvantage, various methods of treating paper products have been suggested in the past. Thus, wet strength can be increased byparchmentizing paper in sulfuric acid' solution or by surface-sizingwith animal glue and exposing the glue-sized sheet to high temperaturesor to a tanning agent to render the protein insoluble in water.Additionally, various resins such as the urea-formaldehyde andmelamine-formaldehyde resins, among others, have been employed toenhance wet strength. Many of these prior art methods suffer fromserious disadvantages. Thus, the absorbency of the paper may be reduced,or increased stiifness and harshness result, While in some instances thedeterioration rate of the paper is increased. Moreover, many seriouspractical difficulties have been found to arise in the commercialapplication of such treatments in paper mills.

Resins which are substantive to fibers of hydrated cellulosic materialsuch as aqueous suspensions of papermaking fibers, and can thus bereadily applied in the di lute aqueous suspensions encountered in papermills, are also known to the art. Among the resins of this type whichhave been employed heretofore are (1) resins produced by reaction ofpolyalkylenepolyamines with halohydrins, (2) resins produced by reactingpolyalkylenepolyamines with saturated aliphatic dibasic carboxylic acidsto yield a first stage product with subsequent reaction of this firststage product with a halohydrin and (3) resins produced by reaction ofpolyalkylenepolyamines with unsaturated aliphatic dior polycarboxylicacids, or mononuclear aromatic polycar-boxylic acids, followed byreaction of the resulting polyamide with a halohydrin.

It has now been found that cationic Water-soluble 3,372,086 PatentedMar. 5, 1968 resins that are substantive to paper-making fibers can beproduced by reacting a polyalkylenepolyamine with a saturated aliphaticdialdehyde and then reactin the resulting product with a halohydrin. Thenovel resins prod ced in this manner are capable of providing Wetstrength at least equal to that of any of the resins of the prior art aswell as improving the dry strength of paper and paper products and havebeen found to function effectively at low levels of addition and over aWide pH range. In addition to their use as wet and dry strengthimproving agents, the novel resins disclosed herein find furtherimportant application as retention aids, drainage rate improvers,flocoulents, White water clarifiers, and so forth.

The cationic water-soluble resins of this invention are produced in atwo-stage process. The first stage resin is the product produced byreacting a polyamine with a dialdehyde, while the second stage resin isthe product resulting from partial crosslinking of the first stage resinwith a halohydrin.

The suitable polyamines for the purpose of this invention are thepolyalkylenepolyamines having at least two primary amine groups and atleast one secondary amine group. The nitrogen atoms in such polyaminesare linked by C H groups, wherein m is a small integer such as 2, 3 or4, and the molecule may contain from 2 up to about 8 of such groups.Commercially available polyalkylenepolyamines, Which are mixtures oflinear, branched and cyclic polyalkylenepolyamines, are entirelysuitable for use in producing the novel resinous compositions of thisinvention. Accordingly, the term "polyalkylenepolyamine as employedherein and in the appended claims is intended to includepolyalkylenepolyamines in pure or relatively pure form, mixtures of suchmaterials, and crude polyalkylenepolyamines which are commercialproducts and many contain minor amounts of other compounds. Illustrativeof the suitable polyalkylenepolyamines one can mention thepolyethylenepolyamines such as diethylenetriamine, triethylenetetramine,tetraethylenepentamine, pentaethylenehexamine,N-(Z-aminoethyl)piperazine, N,N bis(2 aminoethyl)-ethylenediamine,diaminoethyl triaminoethylamine, piperazinoethyl triethylenetetramine,and the like. The corresponding polypropylenepolyamines andpolybutylenepolyamines can also be employed although thepolyethylenepolyamines are preferred for economic reasons.

To prepare the first stage resin of this invention, the above-describedpolyalkylenepolyamine is reacted with a saturated aliphatic dialdehydeof 2 to 6 carbon atoms, such as, for example, glyoxal, pyruvic aldehyde,succinaldehyde, glutaraldehyde, or Z-hydroxyadipaldehyde. Thepolyalkylenepolyamine and the dialdehyde are reacted in a proportion ofabout 0.5 to about 2 moles of polyalkylenepolyamine per mole ofdialdehyde at a temperature of about 50 C. to about 20 C. for a periodof at least about 30 minutes, and preferably for a period of at leastabout 60 minutes up to about 6 hours, or more. It is preferred to employa ratio of about 0.8 to about 1.5 moles, of polyalkylenepolyamine permole of dialdehyde and a reaction temperature of about C. to about C.

The first stage resin produced by reaction of a polyalkylenepolyamineand a dialdehyde as described above is partially crosslinked with ahalohydrin to form the second stage resin, with the crosslinking takingplace primarily through secondary amine groups of the first stage resin.In effecting the second stage reaction, the first stage'resin is firstdissolved in water or other suitable diluent such as methanol, ethanol,1,4-dioxane, and the like, and the halohydrin is then slowly added tothe solution. The suitable halohydrins for the purposes of thisinvention are the dihalohydrins such as w'y-dichlorohydrin,

dibromohydrin, and di-iodohydrin and monohalohydrins which contain inaddition to the halogen a functional group, such as an epoxy group,which is capable of combining with an amine group. Illustrative of thislatter class of halohydrins one can mention epichlorohydrin,epibromohydrin, epi-iodohydrin, 1,3-dichloro-2-propanol, 1,3-dibromo-Z-propanol, and the like. For economic reasons and also becauseof the particularly desirable results obtained thereby, it is preferredto employ epichlorohydrin in this invention.

The amount of the polyfunctional halohydrin employed in the second stagereaction is an amount sufficient to provide a molar ratio of halohydrinto secondary amine groups of the first stage resin of about 0.5 to about1.5, and more preferably from about 0.8 to about 1.1. Suitable reactiontemperatures for the second stage reaction are in the range from about20 C., or less, to about 100 C., or more, and preferably within therange from about 40 C. to about 80 C. In carrying out the second stagereaction, the first stage resin is first diluted with a suitablediluent, as described above, to a solids content of from about 5 to 35percent by weight, more preferably from about to 25 percent by weight,and then th polyfunctional halohydrin is added.

The time required for the second stage reaction will vary from arelatively long period such as about 24 hours, or more, at the lowerreaction temperatures to a relatively short period such as about 10minutes, or less, at the higher reaction temperatures. In general, theexothermic second reaction is continued until the product reaches aviscosity in the range between B and E on the Gardner scale, while thepreferred procedure is to terminate the reaction when the viscosityreaches C-Gardner or D- Gardner. This is accomplished by cooling anddiluting the resin, preferably with distilled water, to a solids contentof about percent or less. The dilute resin solution is then stabilizedby adjusting the pH to a value of about 5 or less. This is conventientlyaccomplished by the addition of an appropriate quantity of acid such asconcentrated hydrochloric acid, concentrated sulfuric acid, concentratedphosphoric acid, glacial acetic acid, and the like, or by addition ofgaseous carbon dioxide. A considerable proportion of the second stageresin will consist of inert material, i.e. material that is ineifectivein enhancing wet strength, as a result of the splitting off from thehalohydrin of a hydrogen halide which reacts with the amine groups.

The following reaction equations typify the reactions occurring in thetwo-stage process of preparing the resins of this invention. Equation 1illustrates the initial step in the first stage reaction of glyoxal withtriethylenetetramine while Equation 2 illustrates the subsequent secondstage reaction with epichlorohydrin (illustration of the crosslinkingbeing omitted). In the second stage reaction the epichlorohydrin isshown as reacting with all secondary amine groups and not with theterminal primary amine groups of the molecule but in fact reaction withthe primary amine groups will, of course, also occur.

The second stage resin of this invention is a cationic water-solublethermosetting resin that must be cured to a water-insoluble formsubsequent to its incorporation in a paper product in order to etfect anincrease in wet strength. The curing period required to obtain Wetstrength is dependent on the temperature employed and to a lesser extenton the pH of the paper product. Wet strength may be obtained by allowingthe treated paper to air dry at room temperature for a prolonged period,such as a period of 24 hours or more. Generally, the wet strength willcontinue to increase over about a 30-day period at room temperaturebefore reaching its ultimate value. It is preferred, however, toaccelerate the cure of the resin by heating the treated paper product.Such heating is suitably accomplished in the drying stage in theoperation of a conventional paper-making machine and modification of thenormal drying conditions employed with such machines will not generallybe necessary. Drying conditions encountered in commercial paper machineoperation are, typically, temperatures of about 85 C. to about 135 C.for periods of about 1 to 4 minutes and such conditions are fullycapable of effecting curing of the resins of this invention. Under suchconditions the wet strength will continue to improve over a 20 to 30 dayperiod and ultimately will reach about to percent of the strength thatcould be attained in the laboratory by use of a more prolonged curingperiod at comparable temperatures.

The wet-strength improving resins of this invention can be utilized infelted fibrous cellulosic materials, such as paper, paperboard, andshaped paper articles, formed from any suitable pulp including bleachedand unbleached pulp. Suitable pulp includes sulfite, kraft, soda,groundwood, rag, rope, and jute pulp, etc. The pulp can contain a minoramount of conventional, synthetic paper-making fibers. Conventionalfillers such as, for example, clay, calcium carbonate, titanium dioxide,talc, calcium silicate, barium sulfate, and the like, can also beincorporated in the paper product. The resins are effective in improvingthe Wet strength of paper products when added to the cellulosicpaper-making fibers in small amounts. Thus, the resin can be added in anamount of from about 0.05 percent, or less, to about 5 percent or more,based on the weight of the fibers, and is preferably employed in anamount of from about 0.2 to about 3 percent. The resin can be applied asa tub-size, i.e., an aqueous solution of the resin can be applied to thesheeted paper by dipping, rolling, padding, etc., or at the beater orwet-end stage by introducing the resin to the aqueous paper-makingfurnish at any time prior to sheet formation. The wet-strength papers ofthis invention can be employed in absorbent products such as toweling,facial tissue, and saturating papers and in sized and unsized productsemployed as packaging, paper bags, bond and envelope papers, andpaperboard, or wherever paper of high wet strength finds suitableapplication.

The specific examples which follow are given to further illustrate theinvention, it being understood that these ex- I onoHJ 011,01 2

Lpnon CHzCl amples are not intended to be limiting of the invention butmerely illustrative thereof. Solids content values reported are in allcases in terms of active solids. In each instance thepolyalkylenepolyamine employed was a commercial grade material and thusconsisted of a mixture of linear, branched and cyclic compounds.

Example 1 To a four-necked 500 ml. reaction flask equipped with amechanical stirrer, thermometer, dropping funnel, and condenser therewas charged 0.30 mole of tetraethylenepentamine and then 0.20 mole ofaqueous glyoxal was added dropwise over a 40 minute period, with thetemperature resulting from the exothermic reaction being maintained at40 to 50 C. by controlling the rate of addition. The temperature of thereaction flask was increased gradually and the water stripped off at 150C. After holding the temperature at 150 C. for approximately 2 hours,the resulting resinous reaction product was dissolved in distilled waterand diluted to 20 percent solids. The flask temperature was adjusted toabout 50 C. and then 0.90 mole of epichlorohydrin was added dropwiseover a 40 minute period with the heat of the exothermic reaction beingremoved by cooling so as to maintain the temperature at 50 to 60 C.After completion of the addition of the epichlorohydrin, the solutionwas heated at 75 C. for 1 hour and 30 minutes and at 85 C. for 30minutes and then distilled water was added to dilute to a solids contentoi 3 percent.

Example 2 To the apparatus of Example I there was charged 0.20 mole ofglyoxal hydrate in solid form and the flask was then cooled in anice-bath to C., 0.30 mole of trijusted to C. and 0.65 mole ofepichlorohydrin was added dropwise over a 10 minute period, with theflask being cooled to maintain a temperature of 50 to 60 C. Aftercompletion of the addition of the epichlorohydrin, the solution washeated to 70 to 75 C. for 30 minutes, at which point the solutionviscosity equaled C-Gardner. Distilled water was then added to dilute toa solids content of one percent and the pH was adjusted-to 4.3 byaddition of concentrated hydrochloric acid.

The resins prepared in Examples 1 to 3 above were evaluated as paperwet-strength additives. In the evaluation procedure employed, a sampleof moist pulp (unbleached kraft pulp) of suflicient size to provide 2.61grams of bone dry pulp was diluted with distilled water to a pulpcontent of 1.6 percent by weight. The pulp slurry was then placed in amechanical mixer, the wetstrength resin was added, and the pulp wasagitated for a period of 15 minutes. After the agitation, the pulpslurry was placed in a handsheet mold, suflicient water was added tomake a total slurry of 12 liters and a handsheet was prepared and dried.The resin was cured for a period of 3 hours at a temperature of 105 C.and then the handsheet was conditioned overnight at 23 C. in anatmosphere with 50 percent relative humidity. Tensile strengths, bothwet and dry, were measured on a table model Instron tensile tester; thetensile strength being defined as the force required to break a strip ofpaper having a standard width of 15 millimeters and being reported inkilograms/15 millimeters. The wet tensile strength was determined aftersoaking the sample in water for at least 16 hours. Results of theevaluation are presented in Table I below, with the wet tensile strengthfor a control sample that contained no wet-strength resin being includedfor comparison purposes.

1 Percent by weight of dry pulp based on active solids in resin. 2Weight in pounds of a standard ream containing 500 sheets, each sheetbeing 25 x 38 inches.

8 Percent wet strength=w x100.

ry tensile strength ethylenetetramine was added and the temperature was50 Consideration of the above results indicates that the graduallyincreased to about 50 C. After approximately 10 minutes at 50 C., thereaction rate increased andthe temperature rose rapidly to 90 C. due tothe exothermic reaction. The mixture was stirred until the temperaturedropped to 50 C. and then distilled water was added to dilute to asolids content of 20 percent, and 0.60 mole of epichlorohydrin was addedto the solution in a dropwise manner with the temperature held at 50 to60 C. by cooling. The solution was then heated at 85 C. forapproximately 2 hours and the resulting resin diluted to 3 percentsolids content by addition of distilled water.

Example 3 To the apparatus of Example 1 there was charged 0.24 mole oftetraethylenepentamine and then 0.20 mole of glutaraldehyde, as a 25weight percent aqueous solution, was added dropwise over a 10 minuteperiod with a resulting increase in the temperature to 60 C. because ofthe heat of reaction. After completion of the addition of theglutaraldehyde, the temperature was gradually increased and the waterstripped OE and then the reaction mixture was maintained under a reducedpressure of 100 mm. of Hg and a temperature of 150 C. for 1.5 hours. Theresulting orange-colored resin was dissolved in 220 ml. of distilledwater, the temperature was adnovel resins described herein are highlyeffective wet strength agents for paper and paper products at low levelsof addition. Moreover, these resins function eifectively over a pH rangeof from about 4 to about 10 and can be readily applied to paper andpaper products without changing the operating conditions employed incommercial paper mills.

What is claimed is:

1. The cationic water-soluble resinous reaction product of (a) apolyfunctional halohydrin and (b) a resin produced by reaction of apolyalkylenepolyamine with a saturated aliphatic dialdehyde of 2 to 6carbon atoms.

2. The cationic water-soluble resinous reaction product of (a) apolyfunctional halohydrin and (b) a resin produced by reaction at atemperature of about 50 C. to about 200 C. of about 0.5 to about 2 molesof polyalkylenepolyamine per mole of a saturated aliphatic dialdehyde of2 to 6 carbon atoms, the molar ratio of said polyfunctional halohydrinto secondary amine groups of said resin being from about 0.5 to about1.5 and the reaction of said polyfunctional halohydrin and said resinbeing conducted at a temperature of from about 20 C. to about C.

3. Thecationic Water-soluble resinous reaction product of (a) apolyfunctional halohydrin and (b) a resin produced by reaction at atemperature of about 80 C. to about 160 C. of about 0.8 to about 1.5moles of polyalkylenepolyamine per mole of a saturated aliphaticdialdehyde of 2 to 6 carbon atoms, the molar ratio of saidpolyfunctional halohydrin to secondary amine groups of said resin beingfrom about 0.8 to about 1.1 and the reaction of said polyfunctionalhalohydrin and said resin being conducted at a temperature of from about40 C. to about 80 C.

4. The cationic Water-soluble resinous reaction product of (a)epichlorohydrin and (b) a resin produced by reaction at a temperature ofabout 80 C. to about 160 C. of about 0.8 to about 1.5 moles of apolyalkylenepolyamine selected from the group consisting oftriethylenetctramine and tetraethylenepentamine per mole of glyoxal, themolar ratio of epichlorohydrin to secondary amine groups of said resinbeing from about 0.8 to about 1.1 and the reaction of epichlorohydrinand said resin being conducted at a temperature of from about 40 C. toabout 80 C.

5. The cationic Water-soluble resinous reaction product of (a)epichlorohydrin and (b) a resin produced by reaction at a temperature ofabout 80 C. to about 160 C. of about 0.8 to about 1.5 moles oftetraethylenepentamine per mole of glutaraldehyde, the molar ratio ofepichlorohydrin to secondary amine groups of said resin being from about0.8 to about 1.1 and the reaction of epichlorohydrin and said resinbeing conducted at a temperature of from about 40 C. to about 80 C.

6. In the manufacture of paper products from cellulosic paper-makingfibers, the improvement which comprises incorporating in said fibersfrom about 0.05 to about 5 percent, based on the weight of said fibers,of a cationic water-soluble resinous reaction product of (a) apolyfunctional halohydrin and (b) a resin produced by reaction of apolyalkylenepolyamine with a saturated aliphatic dialdehyde of 2 to 6carbon atoms and subsequently curing said resinous reaction product to awater-insoluble form.

7. In the manufacture of paper products from cellulosic paper-makingfibers, the improvement which comprises incorporating in said fibersfrom about .05 to about percent, based on the weight of said fibers, ofa cationic water-soluble resinous reaction product of (a) apolyfunctional halohydrin and (b) a resin produced by reaction at atemperature of about 50 C. to about 200 C. of about 0.5 to about 2 molesof polyalkylenepolyamine per mole of a saturated aliphatic dialdehyde of2 to 6 carbon atoms, the molar ratio of said polyfunctional halohydrinto secondary amine groups of said resin being from about 0.5 to about1.5 and the reaction of said polyfunctional halohydrin and said resinbeing conducted at a temperature of from about 20 C. to about 100 C.,and subsequently applying heat to cure said resinous reaction product toa water-insoluble form.

8. In the manufacture of paper products from cellulosic paper-makingfibers, the improvement which comprises incorporating in said fibersfrom about 0 .2 to about 3 percent, based on the weight of said fibers,of a cationic water-soluble resinous reaction product of (a) apolyfunctional halohydrin and (b) a resin produced by reaction at atemperature of about 80 C. to about 160 C. of about 0.8 to about 1.5moles of polyalkylenepolyamine per mole of a saturated aliphaticdialdehyde of 2 to 6 carbon atoms, the molar ratio of saidpolyfunctional halohydrin to secondary amine groups of said resin beingfrom about 0.8 to about 1.1 and the reaction of said polyfunctionalhalohydrin and said resin being conducted at a temperature of from about40 C. to about 80 C., and subsequently applying heat to cure saidresinous reaction product to a water-insoluble form.

9. In the manufacture of paper products from cellulosic paper-makingfibers, the improvement which comprises incorporating in said fibersfrom about 0.2 to about til 3 percent, based on the weight of saidfibers, of a cationic water-soluble resinous reaction product of (a)epichlorohydrin and (b) a resin produced by reaction at a temperature ofabout C. to about C. of about 0.8 to about 1.5 moles of apolyalkylenepolyamine selected from the group consisting oftriethylenetetramine and tetraethylenepentamine per mole of glyoxal, themolar ratio of epichlorohydrin to secondary amine groups of said resinbeing from about 0.8 to about 1.1 and the reaction of epichlorohydrinand said resin being conducted at a temperature of from about 40 C. toabout 80 C., and subsequently applying heat to cure said resinousreaction product to a Water-insoluble form.

10. In the manufacture of paper products from cellulosic paper-makingfibers, the improvement which comprises incorporating in said fibersfrom about 0.2 to about 3 percent, based on the weight of said fibers,of a cationic water-soluble resinous reaction product of (a)epichlorohydrin and (b) a resin produced by reaction at a temperature ofabout 80 C. to about 160 C. of about 0.8 to about 1.5 moles oftetraethylenepentamine per mole of glutaraldehyde, the molar ratio ofepichlorohydrin to secondary amine groups of said resin being from about0.8 to about 1.1 and the reaction of epichlorohydrin and said resinbeing conducted at a temperature of from about 40 C. to about 80 C., andsubsequently applying heat to cure said resinous reaction product to aWater-insoluble form.

11. A paper product of improved wet strength comprising cellulosicpaper-making fibers containing from about 0.0 5 to about 5 percent,based on the weight of said fibers, of a cationic resinous compositionobtained by reacting (a) a polyfunctional halohydrin with (b) a resinproduced by reaction of a polyalkylenepolyamine with a saturatedaliphatic dialdehy-de of 2 to 6 carbon atoms, to produce a water-solublereaction product and subsequently curing said reaction product to awater-insoluble form.

12. A paper product of improved wet strength comprising cellulosicpaper-making fibers containing from about 0.2 to about 3 percent, basedon the weight of said fibers, of a cationic resinous compositionobtained by reacting (a) a polyfunctional halohydrin with (b) a resinproduced by reaction at a temperature of about 80 C. to about 160 C. ofabout 0.8 to about 1.5 moles of polyalkylenepolyamine per mole of asaturated aliphatic dialdehyde of 2 to 6 carbon atoms, the molar ratioof said polyfunctinal halohydrin to secondary amine groups of said resinbeing from about 0.8 to about 1.1 and the reaction of saidpolyfunctional halohydrin and said resin being conducted at atemperature of from about 40 C. to about 80 C., to produce awater-soluble reaction product and subsequently applying heat to curesaid reaction product to a Water-insoluble form.

13. A paper product of improved Wet strength comprising cellulosicpaper-making fibers containing from about 0.2 to about 3 percent, basedon the weight of said fibers, of a cationic resinous compositionobtained by reacting (a) epichlorohydrin and (b) a resin produced byreaction at a temperature of about 80 C. to about 160 C. of about 0.8 toabout 1.5 moles of a polyalkylenepolyamine selected from the groupconsist ing of triethylenetetramine and tetraethylenepent-amine per moleof glyoxal, the molar ratio of epichlorohydrin to secondary amine groupsof said resin being from about 0.8 to about 1.1 and the reaction ofepichlorohydrin and said resin being conducted at a temperature of fromabout 40 C. to about 80 C., to produce a water-soluble reaction productand subsequently applying heat to cure said reaction product to aWater-insoluble form.

14. A paper product of improved wet strength comprising cellulosicpaper-making fibers containing from about 0.2 to about 3 percent, basedon the weight of said fibers, of a cationic resinous compositionobtained by reacting (a) epichlorohydrin and (b) a resin produced 9 10by reaction at a temperature of about 80 C. to about applying heat tocure said reaction product to a water- 160 C. of about 0.8 to about 1.5moles of tricthylencinsoluble form. tetramine per mole ofglutaraldehyde, the molar ratio of References Cited epichlorohydrin tosecondary amine groups of said resin being from about 0.8 to about 1.1and the reaction of 5 UNITED STATES PATENTS epichlorohydrin and saidresin being conducted at a tem- 2,926,11 1 0 Keim 1 4 perature of fromabout 40 C. to about 80 C., to produce a water-soluble reaction productand subsequently S. LEON BASHORE, Primary Examiner.

